How do you find #E^-1# given #E=((1, -1), (1, 1))# ? Precalculus Matrix Algebra Inverse Matrix 1 Answer Eddie Jul 8, 2016 #1/2 ((1,1),(-1,1))# Explanation: #((a,b),(c,d))^-1 =1/(ad - bc) ((d,-b),(-c,a))# here that's #1/(1 * 1 - (-1) * 1) ((1,1),(-1,1))# #1/2 ((1,1),(-1,1))# Answer link Related questions What is the multiplicative inverse of a matrix? How do I use an inverse matrix to solve a system of equations? How do I find an inverse matrix on a TI-84 Plus? How do I find the inverse of a #2xx2# matrix? How do I find the inverse of a #3xx3# matrix? How do I find an inverse matrix on an Nspire? What is the meaning of the phrase invertible matrix? The given matrix is invertible ? first row ( -1 0 0 ) second row ( 0 2 0 ) third row ( 0 0 1/3 ) How do you find the inverse of #A=##((2, 4, 1),(-1, 1, -1), (1, 4, 0))#? How do you find the inverse of #A=##((1, 1, 1, 0), (1, 1, 0, -1), (0, 1, 0, 1), (0, 1, 1, 0))#? See all questions in Inverse Matrix Impact of this question 1648 views around the world You can reuse this answer Creative Commons License